Worm gear escapement



March 7, 1967 v I G. A. DOTTO WORM GEAR ESCAPEMENT 4 Sheets-Sheet 1Filed July 27, 1964 INVENTOR.

0/ N/ A. oorro Wig-w ATT. NEY

March 7, 1967 G. A. DOTTO WORM. GEAR ESGAPEMENI 4 Sheets-Sheet FiledJuly 27, 1964 Match 7, 1967 5. A. DOTTO 3,307,417

WORM GEAR ESCAPEMENT Filed July 27, 1964 4 Sheets-Sheet s INVENTOR.G/A/VN/ A. 00770 FIE. Z BY ATTORNEY Mar'ch7, G A -r0 WORM GEARESCAPEMENT 4 Sheets-Sheet 4 Filed July 27, 1964 NH UHHI INVENTOR.GlA/V/V/ A. Dorm ATTORNEY United States Patent Ofiice 3,307,417 PatentedMar. 7, 1967 3,307,417 WORM GEAR ESCAPEMENT Gianni A. Dotto, Dayton,Ohio, assignor to P. R. Mallory & Co., Inn, Indianapolis, Ind., acorporation of Delaware Filed July 27, 1964, Ser. No. 385,402 7 Claims.(Cl. 74-426) The present invention relates to an escapement, moreparticularly to escapements imparting an intermittent or step-by-steprotary motion output from a substantially constant rotary motion input.Such timed, intermittent rotary motion escapements are employed toperiodically actuate control devices such as a switch means that in turnregulates the time sequence of operations embodied in washing machinesand other similar devices.

In a device of this general nature, it is desirable that the escapementbe actuated after a predetermined interval of time has elapsed. Theescapement operates a control device such as a switch means having as acomponent thereof a series of cam operated switches. The

escapement with which the present invention is concerned is of the typehaving a substantially constant rotary motion input which is translatedby the novel escapement into an intermittent, snap rotary motion output.The device would necessarily include a drive motor, a drive gear, anescapement, and a switch means that sequentially actuates a plurality ofelectrical circuits.

In control timer utilizing escapements, it is desirable that the timerbe manually operable to modify the duration or sequence of operation byeither shortening or skipping over the particular operations entirely.For this purpose the novel timer of the present invention is providedwith a manually operable means coupled to a cam shaft so that anoperator is able to modify the duration or sequence of operations of thetimer in accordance with the desires of the operator.

Severalescapements presently available impart an intermittent orstep-by-step snap rotary motion output from a substantially constantrotary motion input and are used in conjunction with a switch means toform a control timer. These several escapements utilize means forstorage of energy during a first portion of a cycle, the storage cycle,and/or subsequently releasing the stored energy so stored during asecond portion of the cycle, the release cycle. Generally, theseescapements are satisfactory for limited purposes and are usually bulkyand complicated and slow in operation. In the typical escapement thedriving force is stored for a predetermined interval of time by a leafspring that is either expanded or compressed thus storing energy. Whenthe leaf spring is released from its expanded or from its compressedcondition, the energy so stored provides a driving torque for a ratchetwheel and its associated driving means.

The use of an intermittent driving means provides the facility ofperiodic actuation of a particular event but in addition the drivingmeans provides a method whereby switch contacts are displaced from afirst contact to a second contact with such velocity that the contactsare not damaged for arcing does not occur between the contacts. Arcingoccurs when a switch contact is slowly withdrawn from engagement with afirst contact. It is seen the intermittent release of stored energy overa relatively short period of time is transferred to a ratchet wheel andthen to a cam operated means which means controls the sequentialoperation of a plurality of switch devices.

The present invention provides an intermittent driving means whereby theleaf spring is replaced by a worm gear mechanism that is a simple,efficient, inexpensive, accurate, effective means that provides anintermittent driving force that regulates the sequential operation of acontrol timer.

Therefore, it is an object of the present invention to provide a novelrotary motion translating means utilized to translate a slow, continuousrotary motion to a rapid, intermittent rotary motion.

Another object of the present invention is to provide an escapementmeans that has a more positive, high velocity intermittent drivingforce.

Yet another object of the present invention is to provide an escapementin which each impulse or jump has a precise amount of travel withoutovertravel.

Another object of the present invention is to provide a novel worm gearescapement mechanism for actuating a plurality of multicontact electricswitches, the worm gear escapement being inexpensive and accurate inconstruction, and more positive in its driving force.

Yet another object of the present invention is to provide a worm gearescapement mechanism having a pin driven in planetary fashion overcamming surfaces which camming surfaces include rise and fall contourswhich cona plurality of multi-contact switches, the escapement havingoptimum reliability characteristics afforded by a construction having aminimum number of components.

The present invention in another of its aspects, rel-ates to novelfeatures of the instrumentalities of the invention described therein forteaching the principal object of the invention and to the novelprinciples employed in. the instrumentalities whether or not thesefeatures and principles may be used in the said object and/ or in thesaid field.

With the aforementioned objects enumerated, other objects will beapparent to those persons possessing ordinary skill in the art. Otherobjects will appear in the following description, appended claims, andappended drawings. The invention resides in the novel construction,combination arrangement and cooperation of elements as hereinafterdescribed and more particularly as defined in the appended claims.

The appended drawings illustrate several novel and different embodimentsof the present invention and are constructed to function in the mostadvantageous modes devised for the practical application of the basicprinciples involved in the hereinafter described invention.

In the drawings:

FIGURE 1 is a perspective view of the present invention illustrating thenovel worm gear mechanism.

FIGURE 2 is an enlarged sectional view of the present inventionillustrating the worm gear mechanism in its initial position takenacross the lines 2--2 of FIGURE 1.

FIGURE 3 is an enlarged sectional view of the present inventionillustrating the worm gear immediately 3 prior to the actuation of aratchet by the worm gear taken across the lines 2-2 of FIGURE 1.

FIGURE 4 is an enlarged sectional view of the present inventionillustrating the worm gear immediately subsequent to the actuation of aratchet by the worm gear taken across the lines 22 of FIGURE 1.

FIGURE 5 is an enlarged top view with portions thereof cut away of anembodiment of the present invention illustrating a shaft carrying aBelleville washer and showing the movement of the shaft and associatedwasher in full and dotted lines respectively.

FIGURE 6 is an enlarged top view with portions thereof cut away of theembodiment of FIGURE 5 illustrating the position of the shaft andassociated Belleville washer immediately prior to the intermittent,forward movement of the shaft.

FIGURE 7 is an enlarged sectional view of another embodiment of thepresent invention illustrating an arm actuating means.

FIGURE 8 is an enlarged partial front view of the present inventionillustrating a shaft incorporating therein an off center shaft and anassociated pin to provide an actuating means, the intermittent movementof which is illustrated in full and dotted lines respectively.

FIGURE 9 is an enlarged sectional view of the invention of FIGURE 8illustrating the off center actuating means and a cooperating tensionspring, the sectional view taken across the lines 99 of FIGURE 8.

FIGURE 10 is an enlarged perspective view of the actuating means ofFIGURE 8.

Generally speaking, the means and methods of the present inventionrelate to escapements for timing devices through the use of which it ispossible to selectively control the sequential operation of a pluralityof cam operated switches. The escapement of the present inventionutilizes a drive means for providing a substantially constant rotarymotion output. A gear reduction means is coupled to the drive means toeffectively reduce the rotary motion output of the drive means to aprede termined speed. An escapement, more particularly a worm gearescapement, is mechanically coupled to the gear reduction means. Theescapement includes an actuating means, preferably a shaft rotatable ina predetermined direction. A coded indicia follower means, preferably apin, is fixedly coupled to the shaft and rotatable therewith. Aplurality of coded indicia, preferably cams, are positioned concentricwith the axis of the shaft. The coded indicia have rise and fallperipheral contours which the pin traverses as the shaft to which it iscoupled rotates. As the shaft rotates, a tension spring means iscompressed thereby storing energy as the pin rises along the risecontours of the cams as a result of the rotation of the shaft. Thecompressed tension spring releases the v stored energy as the pin fallsalong the fall contours of the cams. A worm gear coupled to the shaftprovides a driving force to a ratchet means as the pin falls along thefall contours of the cams.

More particularly, the present invention relates to a worm gearescapement including a mounting means and a retaining means pivotablycoupled to the mounting means; the retaining means carrying a shaftrotatably journalled thereto. A coded indicia follower means, preferablya pin, is fixedly coupled to the shaft and is rotatable with the shaft.A plurality of coded indicia, preferably cams, are fixedly coupled tothe retaining means at a right angle to the longitudinal axis of theshaft. Each of the cams are concentric with the shaft and each of thecams has an arcuate extent of about 180 degrees. The cams includealternate rise and fall peripheral contours upon which the pin rides asthe shaft rotates. A tension spring wound about the shaft is compressedas the pin rises on the rise contour of the cams thereby storing energy.The compressed tension spring releases the I stored energy as the pinfalls along the fall contours of the cams. A worm gear is fixedlycoupled to the shaft.

The worm gear is rotationally displaced as the tension spring iscompressed, however, the rotational displace ment of the worm gear doesnot rotationally displace a ratchet means coupled to the worm gear. Theworm gear is linearly displaced as the stored energy of the tensionspring is released. It is seen that the worm gear does not experience arotational displacement during the release of the stored energy. Theratchet is actuated by the linear displacement of the worm gear so as toprovide a driving torque for an associated cam shaft. The ratchet isdisplaced with an intermittent motion of a predetermined increment andmagnitude. I

Another embodiment of the present invention is an escapement including amounting means and a retaining means pivotably coupled to the mountingmeans. The retaining means has two legs spaced apart in parallelrelationship. A slot of predetermined length and position is cut intoeach leg of the retaining means.- A shaft is rotatably journalled to theretaining means by any suitable means such as planetary bearings or thelike. An off center shaft is milled from the shaft, the off center shafthaving its longitudinal axis spaced apart in parallel relationship tothe longitudinal axis of the shaft. A pin of predetermined length isfixedly coupled to the off center shaft and at a right angle tolongitudinal axis of the off center shaft. The pin and one of theslotsengage so as to prevent displacement of the pin An off centeraperture of a gear interfits with the off center shaft such in such amanner that as the gear is rotated, the off center shaft is displacedthrough an arc whereas the shaft is substantially maintained in aninitial position. A tension spring wound about the shaft and fixedlycoupled thereto has one end coupled to the constantly rotating gear andis compressed as the shaft is maintained in its initial position and thegear rotating thereby storing energy. As the arcuate displacement of thegear approaches degrees from an initial position, the pin disengageswith one of the slots thereby releasing the stored energy of thecompressed spring thereafter rapidly rotating the pin and the shaftthrough an arc of about 180 degrees.- After rotat ing through the arc ofabout 180 degrees, the pin engages the second of the two slots whichslot prevents further rotational displacement. A worm gear is Coupled tothe shaft and rotatable therewith. A ratchet is coupled to the worm ofthe worm gear, the ratchet is actuated by the rotational displacement ofthe worm gear.

Referring now to the drawings, which illustrate the preferredembodiments of the present invention, the es capement apparatus isgenerally indicated by numeral 10. A drive means 11 which can be anysuitable electrical drive means such as an electric motor or the like iscoupled to a rotatable worm gear 12 that is continuously driven in aconstant rotary fashion. It is seen, however, that the drive means ofthe worm gear could be intermittent if desired. Worm gear 12 ispositioned so as to mesh with reduction gear 13 and thereby mechanicallydisplace the reduction gear in the counter-clockwise direction.Reduction gear 13 is fixedly coupled to shaft 14 so that rotationaldisplacement of the reduction gear also rotationally displaces the shaftin a like manner and in a like direction.

A retaining means 15 rotatably journals in its opposite extremitiesshaft 14. It is seen that shaft 14 could have either a floatingcharacteristic with respect to the opposite extremities of the retainingmeans or that the shaft could be rotatably coupled to the extremities byany suitable means such as planetary bearings or the like. The axis ofthe shaft is substantially parallel to the longitudinal axis of theretaining means as shown in FIGURE 1. The extremity of shaft 14 to whichgear 13 is fixedly coupled is retained by end facing 16 of the retainingmeans. Gear 12 is spaced from end facing 16 by the thickness of a washer(not shown). The washer is utilized to prevent the gear fromfrictionally rubbing against the end facing. such friction causing unduegear wear and as a result thereof cause inaccuracies to exist in theescapement. Mounted on the front side of the end facing, the faceopposite the face that abuts the washer, is coded indicia 17. The codedindicia comprises two cams, each cam including alternate rise and fallcontours. The apex of the rise portion of the contour is equal in heightto approximately the distance between the valleys of adjacent teeth ofratchet 18. A coded indicia follower means 19, preferably a pin, issecurely coupled to shaft 14 and is so placed so as to ride on theperiphery of the coded indicia. Pin 19 is perpendicular to and passesthrough the longitudinal axis of the shaft. FIGURE 1 shows that theperiphery of the coded indicia or cams has a rise portion that issubstantially 180- degrees in length. Thereafter the fall portion issubstantially at a right angle to the rise portion thus making the fallportion substantially instantaneous back to an initial position.

As disclosed hereinbefore, pin 19 rides on the periphery of the cams andtherefore the pin will follow the contour of the cams or coded indicia.The rise portion of the coded indicia displaces shaft 14 along itslongitudinal axis in the direction of arrow 20. Also the displacement ofthe shaft is along a line tangent to the periphery of ratchet 18. In sodoing a ring or washer 21 fixedly coupled to shaft 14 compresses tensionspring 22 that is wound about shaft 14 between gear 13 and ring 21.Compression of the tension spring stores energy until such time as theshaft is permitted to return to its initial position at which time thestored energy of the tension spring is released and manifests itself asa driving force for ratchet 18. Shaft 14 is allowed to return to itsinitial position when pin 19 reaches the fall portion of the codedindicia. As pin 19 falls, shaft 14 is displaced in the direction ofarrow 23. In so doing the energy stored by the compression spring isreleased and as a result thereof the shaft is rapidly displaced in thedirection of arrow 23. A worm 24 is fixedly coupled to the extremity ofthe shaft opposite the extremity thereof to which gear 13 is coupled.Worm 24 is rapidly displaced in the direction of arrow 23, as a resultof the rapid displacement of shaft 14. The length of the displacement inthe direction of arrow 23 approximates the length of the fall portion ofthe coded indicia or the cams which as disclosed hereinbefore issubstantially equal to the distance between the adjacent valley portionsof adjacent ratchet teeth of ratchet 18. It is seen that thedisplacement of the ratchet in the clockwise direction approximates thelength of one tooth of the ratchet.

The pitch of the worm 24 is such that as shaft 14 rotates in thecounter-clockwise direction, the displacement of the shaft and the wormin the direction of arrow 25) does not displace ratchet 18 in thecounterclockwise direction. Likewise, because of the pitch of the worm24 and the shape of the mating ratchet teeth, displacement of shaft 14in the direction of arrow 23 will displace ratchet 18 in the clockwisedirection through an are approximately equal to the distance between theadjacent valleys of adjacent ratchet teeth. Pawl 25 is pivotably stakedto mounting frame 26 by any suitable means such as a stake or fixedstud. The pawl interfits with a valley of the ratchet in such a mannerso as to permit motion of the ratchet in the clockwise direction only.The function of the pawl is to prevent displacement of the ratchet inthe counter clockwise direction. Counter-clockwise movement is aretrograde movement which would have a deleterious effect on the abilityof a control timer to perform sequential operations at a predeterminedtime after the initiation of the timing cycle.

A cam shaft 27 is rotatably journalled to the mounting frame by anysuitable means such as by planetary bearings (not shown). Fixedlycoupled to an extremity of the calm shaft is ratchet 18. As ratchet 18is displaced in the clockwise direction by the intermittent movement inthe direction of arrow '23 by worm 24, the cam shaft is like- Wisedisplaced in the clockwise direction. It is seen that the ratchetprovides a driving torque for the cam shaft. Fixedly coupled to the camshaft is a plurality of cams 28 having on their respective peripheriescoded indicia of alternate rise and fall contours. Associated with eachcam is a switch (not shown). The follower arm of a follower switch (notshown) rides on the peripheral contours of a cam and the switch isactuated in accordance with the rise and fall contours of the associatedcam. It is seen that the alternate rise and fall contours control thesequential operation of the switch means.

Retaining means 15 is pivotably coupled to mounting frame 26 byrotatable worm gear 12, the axis of which serves as a pivot point forthe retaining means. As disclosed hereinbefore, gear 12 is coupled todriving means 11 in such a manner that housing 29 of the driving meansoverlies the pivotable point of the retaining means so as to maintainthe retaining means in a predetermined vertical position with respect tomounting frame 26. An L-shaped tab 30 is place-d with an extremity ofthe retaining means containing the worm gear to prevent verticaldisplacement of this portion of the retaining means.

Driving means 11 is securely coupled to mounting frame 26 by anysuitable means such as a plurality of stakes 31. Stakes 31 serve severalpurposes the most obvious of which are to predeterminately seat thedriving means with respect to worm gear 12, to prevent unnecessary anddeleterious oscillation of the housing of the driving means, and toserve as a means to prevent vertical displacement of retaining means 15.

An S-shaped spring 32 has one curved portion thereof seated partiallyaround one of the stakes 31 and a second curved portion thereof seatedpartially around a post 33. An arm 34 of the S-shaped spring overliesthe end of shaft 14 opposite the extremity of the shaft that has thereonworm 24. As disclosed hereinbefore the retaining means is pivotableabout the axis of worm 12. Arm 34 of the S-shaped springs displaces theaxis of the shaft in such manner as to displace worm 24 into engagementwith ratchet 18. In addition when shaft 14 is displaced in the directionof arrow 20, spring 32 has its arm 34 displaced in the direction ofarrow 20 thus storing energy. As shaft 14 is displaced in the directionof arrow 23 the energy so stored by the displacement of the S-shapedspring is released and therefore aids in displacing shaft 14 in thedirection of arrow 23.

FIGURES 2, 3 and 4 more clearly illustrate the operation of the novelescapement. A driving means 11 such as an electric motor rotates theworm gear with a constant rotary motion in the counter-clockwisedirection. Worm gear 12 serves not only to translate the electricalenergy of the motor to a rotatable mechanical energy but in additionserves to reduce the velocity of the mechanical output of the motor.Gear 12 meshes with speed reduc tion gear 13 to rotate the reductiongear in the counterclockwise direction at a predetermined peripheralspeed. Gear 13 is fixedly coupled to a predetermined portion of shaft14, thus the rotating gear rotationally displaces shaft 14 in thecounter-clockwise direction with a constant peripheral speed. As shaft14 is rotated in the counterclockwise direction, pin 19 perpendicular tothe longitudinal axis of the shaft and projecting beyond the outerperiphery of the shaft rides up the rise portion of the coded indicia17. Riding up the coded indicia rotatably displaces not only the pin inthe direction of arrow 20' but also rotatably displaces shaft 14 in thedirection of arrow 20. In so doing tension spring 22 wound around shaft14 is compressed between ring 21 and gear 13 thereby storing energy.Pawl 25 prevents a counter clockwise displacement of the ratchet as worm24 is rotationally displaced in the direction of arrow 20. The codedindicia is broken into two arcuate portions that are concentric aboutthe longitudinal axis of shaft 14. The arcuate extent of each portion ofthe coded indicia is about degrees. The longitudinal displacement of theshaft is equal to the. width of one of the teeth of the ratchet wheel.It is seen that the rise portion of the arcuate portion of the code-dindicia in the longitudinal direction must be substantially equal to thewidth of a ratchet tooth. As pin 19 falls along the fall portion of thecoded indicia, the force stored by the compression spring is released asa driving force that rapidly displaces the shaft in the direction ofarrow 23. Pawl 25 because of its construction and the fabrication of theratchet teeth a driving force acting in the clockwise direction causes aclockwise displacement of the ratchet. Displacement of the ratchetimparts a clockwise driving torque that displaces the cam shaft carryinga plurality of earns 28 which action actuates a plurality of switchesassociated therewith. It is seen that the motion of shaft 14 imparted toratchet 18 as a driving torque is intermittent and at pr determinedintervals.

FIGURE and FIGURE 6 illustrate an embodiment of the present inventionwhereby worm 24 is replaced by a Belleville washer 3S fixedly coupled toshaft 14. In the initial position, the Belleville washer is positionedin a valley between two adjacent ratchet teeth. The major plane of thewasher is perpendicular to the longitudinal axis of shaft 14, thus it isseen that when pin 19 is on the rise portion of the coded indicia, thewasher is displaced in the direction of arrow 20 as well as upwardly asindicated by the dotted lines of FIGURE 5. After the washer passes overthe apex of the ratchet tooth, it falls into the valley of the adjacenttooth. Thereafter the pin falls along the fall contour of the camsreleasing stored energy, which energy acts through the shaft to displacethe ratchet in the clockwise direction as disclosed hereinbefore and asshown in FIGURE 6.

FIGURE 7 illustrates a third embodiment of the present invention whereinshaft 14 is replaced by a non-rotatable arm 36. Coded indicia 17 issecurely coupled to gear 13 by any suitable means such as by pressfitting or by welding. Pin 19 no longer rotates, however, it isperpendicular to the longitudinal axis of the arm as shown in FIGURE 7.As the coded indicia is rotated by gear 13, the pin rides up the riseportion thereof thereby displacing the arm in the direction of arrow 20.As a result of the displacement of the arm in the direction of arrow 20,tip 37 of the arm rides out of the valley between adjacent ratchetteeth. Upon reaching the apex of a ratchet tooth, the tip travelstherealong until it reaches an adjacent valley portion whereupon itfalls into the adjacent valley portion of an adjacent ratchet tooth.Shortly thereafter pin 17 attains the fall portion of the coded indiciaand thereafter falls along the fall portion. This action releases theenergy stored by tension spring 22 displacing arm 35 in the direction ofarrow 23 with a powerful and rapid motion thereby providing a drivingforce. The movement of arm 36 displaces the ratchet in the clockwisedirection, the ratchet providing a driving torque to an associated camshaft. A slot 39 cut in arm 36 interfits with a pin 40. The cooperationof the slot and the pin serves to position the retaining means withrespect to the arm regardless of the position of the arm on the outerperiphery of the ratchet thereby assuring proper cooperation between thevarious elements of the esc-apement.

The fourth embodiment of the present invention is shown in FIGURES 8, 9and 10. An off center shaft 41 is milled from a portion of shaft 14'.The axis of the off center shaft will traverse through an are that hasas its axis, the longitudinal axis of shaft 14. A pin 42 is securelycoupled to the off center shaft and pnojects therefrom at a right angleto the axis of the off center shaft. The pin is of sufficient length tointerfit with a first slot 43 of predetermined length cut in leg 44 ofretaining means The first slot is of sufficient length to permit arcuatemovement by the pin into engagement with the first slot. A second slotas of predetermined length is cut in leg 46 of retaining means 15'. Leg45 is parallel to and predeterminately spaced from leg 44.

a wise direction with a continuous motion.

& Slot 45 is cut into leg 4-6 in such a manner that pin 42 experiencesrotational displacement through an arc of about degrees when the pindisengages slot 43 and engages slot 45 or when pin 42 disengages slot 45and engages slot 43.

A drive means (not shown) can be any suitable electrical drive apparatussuch as an electric motor or the like is coupled to a rotatable wormgear 12 that is con- .tinuously driven in a constant rotary fashion.Worm gear 12 is rotatably positioned on mounting frame 26 to mesh withreduction gear 13. The worm gear mechanically displaces the reductiongear in the counter-clock- Reduction gear 13 carr es a sleeve portion 47that has an off center .aperture 48 that interfits with the off centershaft. An L-shaped slotted portion 49 is cut into the sleeve 47 in sucha manner that tension spring 22 having an end portion 56 that is at aright angle with the longitudinal axis of the spring interfits with theL-shaped slot. Tension spring 22' is comprised of two portions: a firstportion 51 that is tightly wound about shaft 14 and a second portion 52that is loosely wound about shaft 14. The tightly wound first portion ofthe tension spring positions the spring on shaft 14 whereas the looselywound second portion serves to store rotational energy as the endportion 50 of the tension spring is rotationally displaced from aninitial position. It is seen that since the gear and associated sleevehave a substantially floating characteristic on shaft 14' displacementof the gear and associated sleeve rotationally displaces end portion 5%of the tension spring without rotationally displacing shaft 14'. As endportion 5% is displaced in the counterclockwise direction, energy isstored by the second end portion of the tension spring. Although gear 13substantially floats on shaft 14' aperture 48 displaces the axis of theoff center shaft through a predetermined are that has as its axis thelongitudinal axis of shaft 14. As shown in FIGURE 8 and FIGURE 9 as gear13 is rotationally displaced in the counterclockwise direction, endportion 50 of the tension spring is also rotationally displaced. Pin 42interfitting with slot 43 prevents shaft 14' from being rotationallydisplaced. Additional rotational displacement of end portion 50 furtherserves to store additional energy in the tension spring. As disclosedhereinbefore, aperture 48 r is positioned off center in the sleeve ofthe gear so as to interfit with the off center shaft 41. It is seen thatas gear 13' is rotationally displaced, aperture 48 displaces the offcenter shaft through a predetermined arc. Displacement of the shaftthrough the predetermined are gradually displaces pin 42 carried by theoff center shaft in the direction of arrow 53. Displacement of the pinin the direction of arrow 53 gradually withdraws the pin from slot 43.As the off center shaft approaches an arcuate displacement ofapproximately 180 degrees, the pin disengages slot 43. Energy stored inthe tension spring is released thereby rapidly displacing shaft 14' inthe counterclockwise direction as illustrated by the dotted lines ofFIGURE 8. Pin 42 after displacement through an arc of about 180 degreesengages slot 45. The engagement of the pin with slot 45 prevents furtherarcuate displacement of the pin. It is seen that since the off centershaft is an integral part of shaft 14 the shaft is likewise displacedthrough an arc of about 180 degrees providing a driving force forratchet 18. A wonm 24 on shaft 14' is displaced 180 degrees therebyrotationally displacing ratchet 18 in the clockwise directionapproximately through an arc of about one tooth. The ratchet provides adriving torque to an associated cam shaft.

Further rotational displacement of the gear 13 displaces aperture 48thereby arcuately displacing off center shaft 41. Pin 42 is displaced inthe direction of arrow 54. As the off center shaft approaches an arcuatedisplacement of approximately 180 degrees, the pin disengages slot 45.Energy stored in the tension spring is released thereby rapidlydisplacing shaft 14' in the counter-clockwise di- 9 rection. Pin 42after displacement through an arc of about 180 degrees engages slot 43.The engagement of the pin with slot 43 prevents further arcuatedisplacement of the pin. As as the pin is rapidly displaced through anarc of about 180 degrees, shaft 14' is likewise displaced through an arcof about 180 degrees. The ratchet associated with the worm is advancedin the clockwise direction through an are equal to about one ratchettooth. Cam shaft 27 and cam 28 are likewise displaced in the clockwisedirection through an arc equal to about one ratchet tooth.

While the invention is illustrated and described in its preferredembodiments, it will be understood that modifications and variations maybe effected without departing from the scope of the novel concepts ofthis invention as set forth in the appended claims.

Having thus described my invention, I claim:

1. In a control timer, an escapement means for intermittently displacingan integrally connected ratchet wheel and cam carrying shaft comprisinga mounting frame, drive means fixedly connected to said mounting frameproviding a substantially constant rotary motion output, a worm gearescapement means connected to and driven by said drive means, saidescapement including retaining means having one end thereof pivotallyconnected to said mounting frame and a free end, said retaining meansincluding end facings supporting an axially di-splaceable and rotatableshaft, cam follower means fixedly connected to said shaft and rotatabletherewith, cam means carried by one of said end facings including riseand fall contours, said follower means riding on said, contours of saidcam means as said shaft rotates, spring means carried by said shaft forstoring energy as said shaft is axially displaced in a first directiondue to said follower means rising along said rise contours of said cammeans, and worm gear means carried by said shaft rotatably meshing witha ratchet wheel of an integrally connected ratchet wheel and camcarrying shaft so as to have no rotational effect on said ratchet wheeland said cam carrying shaft as said worm gear is rotationally displacedand axially displaced in said first direction, said energy stored insaid spring means released as said follower means falls along said fallcontours of said cams causing said worm gear to be axially displaced ina second direction so as to engage with and advance said ratchet wheeland said cam carrying shaft with an intermittent motion of determinedincrements, and means including said integrally connected ratchet wheeland carrying shaft for pivotally displacing said Worm gear escapementout of mesh with said ratchet wheel as said cam shaft is manuallydisplaced thereby allowing said cam carrying shaft to be rotatablydisplaced independent of said worm gear escapement to a desiredposition.

2. In a control timer, an escapement means for intermittently displacingan integrally connected ratchet wheel and cam carrying shaft comprisinga mounting frame, a drive means fixedly connected to said mounting frameproviding a substantially constant rotary motion output, a worm gearescapement means connected to and driven by said drive means, saidescapement including retaining means having one end thereof pivotallyconnected to said mounting frame and a free end, said retaining meansincluding end facings supporting an axially displaceable and rotatableshaft, cam follower means fixedly connected to said shaft and rotatabletherewith, cam means carried by one of said end facings concentric withsaid shaft including rise and fall contours, said follower means ridingon said contours of said cam means as said shaft rotates, spring meanscarried by said shaft for storing energy as said shaft is axiallydisplaced in a first direction due to said follower means rising alongsaid rise contours of said cam means, and worm gear means carried bysaid shaft rotatably meshing with a ratchet wheel of an integrallyconnected ratchet wheel and cam carrying shaft so as to have norotational effect on said ratchet wheel and cam carrying shaft as saidWorm gear is rotationally displaced and axially displaced in said firstdirection, said energy stored in said spring means released as saidfollower means falls along said fall contours of said cams causing saidWorm gear to be axially displaced in a second direction so as to engagewith and advance said ratchet wheel and said cam carrying shaft with anintermittent motion of determined increments, and means including saidintegrally connected ratchet wheel and carrying shaft for pivotallydisplacing said worm gear escapement out of mesh with said ratchet wheelas said cam shaft is manually displaced thereby allowing said camcarrying shaft to be rotatably displaced independent of said worm gearescapement to a desired position.

3. In a control timer, an escapement means for intermittently displacingan integrally connected ratchet wheel and cam carrying shaft comprisinga mounting frame, a drive means fixedly connected to said mounting frameproviding a substantially constant rotary motion output, a worm gearescapement means connected to and driven by said drive means, saidescapement including retaining means having one end thereof pivotallyconnected to said mounting frame and a free end, said retaining meansincluding end facings supporting an axially displaceable and rotatableshaft, cam follower means fixedly connected to said shaft and rotatabletherewith, cam means carried by one of said end facings including riseand fall contours, said follower means riding on said contours of saidcam means as said shaft rotates, tension spring means carried by saidshaft for storing energy as said shaft is axially displaced in a firstdirection due to said follower means rising along said rise contours ofsaid cam means, and worm gear means carried by said shaft rotatablymeshing with a ratchet wheel of an integrally connected ratchet wheeland cam carrying shaft so as to have no rotational effect on saidratchet wheel and said cam carrying shaft as said worm gear isrotationally displaced and axially displaced in said first direction,said energy stored in said tension spring released as said followermeans falls along said fall contours of said carns causing said wormgear to be axially displaced in a second direction so as to engage withand advance said ratchet wheel and said cam carrying shaft with anintermittent motion of determined increments, means including saidintegrally connected ratchet wheel and carrying shaft for pivotallydisplacing said worm gear escapement out of mesh with said ratchet wheelas said cam shaft is manually displaced thereby allowing said camcarrying shaft to be rotatably displaced independent of said worm gearescapement to a desired position and spring means biasing said worm gearinto engagement with said ratchet Wheel.

4. In a control timer, an escapement means for intermittently displacingan integrally connected ratchet wheel and cam carrying shaft comprisinga mounting frame, a drive means fixedly connected to said mounting frameproviding a substantially constant rotary motion output, a worm gearescapement means connected to and driven by said :drive means, saidescapement including retaining means having one end thereof pivotallyconnected to said mounting frame and a free end, said retaining meansincluding facings supporting an axially displaceable and rotatableshaft, cam follower means fixedly connected to said shaft and rotatabletherewith, cam means carried by said end facings located at saidpivotally connected end of said retaining means, said cams concentricwith said shaft and including rise and fall cont-ours, said followermeans riding on said contours of said cams as said shaft rotates, springmeans carried by said shaft for storing energy as said shaft is axiallydisplaced in a first direction due to saidfollower means rising alongsaid rise contours of said cam means, and worm gear means carried by theextremity of said shaft supported by said end facing at said free end ofsaid retaining means, said worm gear rotatably meshing with a ratchetwheel of an integrally connected ratchet wheel and cam carrying shaft soas to have no rotational effect on said ratchet wheel and said camcarrying shaft as said worm gear is rotationally displaced and axiallydisplaced in said first direction, said energy stored in said springmeans released as said foll-ower means falls along said fall contours ofsaid cams causing said worm gear to be axially displaced in a seconddirection so as to engage with and advance said ratchet wheel and saidcam carrying shaft with an intermittent motion of determined increments,and means including said integrally connected ratchet wheel and carryingshaft for pivotally displacing said worm gear escapement out of meshwith said ratchet wheel as said cam shaft is manually displaced therebyallowing said cam carrying shaft to be rotatably displaced independentof said worm gear escapement to a desired position.

5. In a control timer, an escapement means for intermittently displacingan integrally connected ratchet wheel and cam carrying shaft comprisinga mounting frame, a drive means fixedly connected to said mounting frameproviding a substantially constant rotary motion output, gear reductionmeans connected to said drive means reducing said rotary motion outputof said drive means to a predetermined speed, a worm gear escapementmeans connected to and driven by said gear reduction means, saidescapement including retaining means having one end thereof pivotallyconnected to said mounting frame and a free end, said retaining meansincluding a pair of end facings in spaced parallel relationship, saidend facings supporting an axially displa-ceable and rotatable shaft, camfollower means fixedly connected to said shaft and rotatable therewith,at least two cams carried by said end facings located at said pivotallyconnected end of said retaining means, said cams concentric with saidshaft and having an arcuate extent of about 180 and including rise andfall contours, said follower means riding on said contours of said camsas said shaft rotates, a tension spring means carried by said shaft forstoring energy as said shaft is axially displaced in a first directiondue to said follower means rising along said rise contours of said cams,and worm gear means carried by the extremity of said shaft supported bysaid end facing at said free end of said retaining means, said worm gearrotatably meshing with a ratchet wheel of an integrally connectedratchet wheel and cam carrying shaft so as to have no rotational effecton said ratchet wheel and said cam carrying shaft as said worm gear isrotationally displaced and axially displaced in said first direction,said energy stored in said tension spring released as said followermeans falls along said fall contours of said cams causing said worm gearto be axially displaced in a second direction so as to engage with andadvance said ratchet wheel and said cam carrying shaft with anintermittent motion of determined increments, and means including saidintegrally connected ratchet wheel and carrying shaft for pivotallydisplacing said worm gear escapement out of mesh with said ratchet Wheelas said cam shaft is manually displaced thereby allowing said camcarrying shaft to be rotatably displaced independent of said worm gearescapement to a desired position.

6. In a control timer, an escapement means for intermittently displacingan integrally connected ratchet wheel and cam carrying shaft comprisinga mounting frame, a drive means fixedly connected to said mounting frameproviding a substantially constant rotary motion output, gear reductionmeans connected to said drive means reducing said rotary motion outputof said drive means to a predetermined speed, a worm gear escapementmeans connected to and driven by said gear reduction means, saidescapement including retaining means having one end thereof pivotallyconnected to said mounting frame and a free end, said retaining meansincluding a pair of end facings in spaced parallel relationship, saidend facings supporting an axially displaceable and rotatable shaft, camfollower means fixedly connected to said shaft and rotatable therewith,at least two cams carried by said end facings located at said pivotallyconnected end of said retaining means, said cams concentric with saidshaft and having an arcuate extent of about and including rise and fallcontours, said follower means riding on said cont-ours of said cams assaid shaft rotates, a tension spring means carried by said shaft forstoring energy as said shaft is axially displaced in a first directiondue to said follower means rising along said rise contours of said cams,and worm gear means carried by the extremity of said shaft supported bysaid end facing at said free end of said retaining means, said worm gearrotatably meshing with a ratchet wheel of an integrally connectedratchet wheel and cam carrying shaft so as to have no rotational effecton said ratchet wheel and said cam carrying shaft as said worm gear isrotationally displaced and axially displaced in said first direction,said energy stored in said tension spring released as said followermeans falls along said fall contours of said cams causing said worm gearto be axially displaced in a second direction so as to engage with andadvance said ratchet wheel and said cam carrying shaft with anintermittent motion of determined increments, means including saidintegrally connected ratchet wheel and carrying shaft for pivotallydisplacing said worm gear escapement out of mesh with said ratchet wheelas said cam shaft is manually displaced thereby allowing said camcarrying shaft to 'be rotatably displaced independent of said worm gearescapement to a desired position, and spring means biasing said wormgear into engagement with said ratchet wheel.

7. In a control timer, an escapement means for intermittently displacingan integrally connected ratchet wheel and cam carrying shaft comprisinga mounting frame, a drive means fixedly connected to said mounting frameproviding a substantially constant rotary motion out-put, gear reductionmeans connected to said drive means reducing said rotary motion outputof said drive means to a predetermined speed, a worm gear escapementmeans connected to and driven by said gear reduction means, saidescapement including retaining means having one end thereof pivotallyconnected to said mounting frame and a free end, said retaining meansincluding a pair of end facings in spaced parallel relationship, saidend facings supporting an axially displaceable and rotatable shaft, camfollower means fixedly connected to said shaft and rotatable therewith,at least two cams carried by said end facings located at said pivotallyconnected end of said retaining means, said cams concentric with saidshaft and having an arcuate extent of about 180 and including rise andfall contours, said follower means riding on said contours of said camsas said shaft rotates, a tension spring means carried by said shaft forstoring energy as said shaft is axially displaced in a first directiondue to said follower means rising along said rise contours of said cams,and worm gear means carried by the extremity of said shaft supported bysaid end facing at said free end of said retaining means, said worm gearrotatably meshing with a ratchet wheel of an integrally connectedratchet wheel and cam carrying shaft so as to have no rotational effecton said ratchet wheel and said cam carrying shaft as said worm gear isrotationally displaced and axially displaced in said first direction,said energy stored in said tension spring released as said followermeans falls along said fall contours of said cams causing said worm gearto be axially displaced in a second direction so as to engage with andadvance said ratchet wheel and said cam carrying shaft with anintermittent motion of determined increments, means including saidintegrally connected ratchet wheel and carrying shaft for pivotallydisplacing said worm gear escapement out of mesh with said ratchet wheelas said cam shaft is manually displaced thereby allowing said carncarrying shaft to be rotatably displaced independent of said worm gearescapement to a desired position, tab means for-med from said mountingframe and overlying said free end of said retaining means substantiallypreventing vertical movement of said retaining means, and spring meanshaving one end fixedly connected to said mounting frame and the otherend 13 thereof abutting said shaft biasing said worm gear into 2,739,485engagement with said ratchet Wheel. 2,753,406 2,891,405 References Citedby the Examiner 2,904,728

UNITED STATES PATENTS 5 2,237,108 1 4/1941 Nichols 74426 2,636,5884/1953 Grea et a1. 741.5

14 Sengebusch 74-1.5 X Pigman 74426 X Elmore 74--1.5 Staggs 741.5 X

DAVID J. WILLIAMOWSKY, Primary Examiner.

C. I. HUSAR, Assistant Examiner.

1. IN A CONTROL TIMER, AN ESCAPEMENT MEANS FOR INTERMITTENTLY DISPLACINGAN INTERGRALLY CONNECTED RATCHET WHEEL AND CAM CARRYING SHAFT COMPRISINGA MOUNTING FRAME, DRIVE MEANS FIXEDLY CONNECTED TO SAID MOUNTING FRAMEPROVIDING A SUBSTANTIALLY CONSTANT ROTARY MOTION OUTPUT, A WORM GEARESCAPEMENT MEANS CONNECTED TO AND DRIVEN BY SAID DRIVE MEANS, SAIDESCAPEMENT INCLUDING RETAINING MEANS HAVING ONE END THEREOF PIVOTALLYCONNECTED TO SAID MOUNTING FRAME AND A FREE END, SAID RETAINING MEANSINCLUDING END FACINGS SUPPORTING AN AXIALLY DISPLACEABLE AND ROTATABLESHAFT, CAM FOLLOWER MEANS FIXEDLY CONNECTED TO SAID SHAFT AND ROTATABLETHEREWITH, CAM MEANS CARRIED BY ONE OF SAID END FACINGS INCLUDING RISEAND FALL CONTOURS, SAID FOLLOWER MEANS RIDING ON SAID CONTOURS OF SAIDCAM MEANS AS SAID SHAFT ROTATES, SPRING MEANS CARRIED BY SAID SHAFT FORSTORING ENERGY AS SAID SHAFT IS AXIALLY DISPLACED IN A FIRST DIRECTIONDUE TO SAID FOLLOWER MEANS RISING ALONG SAID RISE CONTOURS OF SAID CAMMEANS, AND WORM GEAR MEANS CARRIED BY SAID SHAFT ROTATABLY MESHING WITHA RATCHET WHEEL OF AN INTEGRALLY CONNECTED RATCHET WHEEL AND CAMCARRYING SHAFT SO AS TO HAVE NO ROTATIONAL EFFECT ON SAID RATCHET WHEELAND SAID CAM CARRYING SHAFT AS SAID WORM GEAR IS ROTATIONALLY DISPLACEDAND AXIALLY DISPLACED IN SAID FIRST DIRECTION, SAID ENERGY STORED INSAID SPRING MEANS RELEASED AS SAID FOLLOWER MEANS FALLS ALONG SAID FALLCONTOURS OF SAID CAMS CAUSING SAID WORM GEAR TO BE AXIALLY DISPLACED INA SECOND DIRECTION SO AS TO ENGAGE WITH AND ADVANCE SAID RATCHET WHEELAND SAID CAM CARRYING SHAFT WITH AN INTERMITTENT MOTION OF DETERMINEDINCREMENTS, AND MEANS INCLUDING SAID INTEGRALLY CONNECTED RATCHET WHEELAND CARRYING SHAFT FOR PIVOTALLY DISPLACING SAID WORM GEAR ESCAPEMENTOUT OF MESH WITH SAID RATCHET WHEEL AS SAID CAM SHAFT IS MANUALLYDISPLACED THEREBY ALLOWING SAID CAM CARRYING SHAFT TO BE ROTATABLYDISPLACED INDEPENDENT OF SAID WORM GEAR ESCAPEMENT TO A DESIREDPOSITION.